The subject matter disclosed herein relates generally to sensors that may be used to provide position and orientation information for an instrument, implant or device used in a medical context, such as in a surgical or interventional context. In particular, the subject matter relates to a sensor assembly sized to fit within a medical instrument, implant or device.
In various medical contexts it may be desirable to acquire position and/or orientation information for a medical instrument, implant or device that is navigated or positioned (externally or internally) relative to a patient. For example, in surgical and/or interventional contexts, it may be useful to acquire position and/or orientation information for a medical device, or portion of a medical device, even when the device or relevant portion is otherwise out of view, such as within a patient's body. Likewise, in certain procedures where an imaging technique is used to observe all or part of the position and orientation information, it may be useful to have position and orientation information derived from the tracked device itself that can be related to the image data also being acquired.
One issue that can arise with respect to navigation sensors suitable for acquiring position and orientation information in this manner is the size of the position and orientation sensor relative to the device that is to be tracked. In particular, in surgical and interventional contexts, it may be desired to use an instrument, implant or device that is as small as possible, either due to the size and/or fragility of the anatomy undergoing the procedure or to otherwise minimize the trauma associated with the procedure. Therefore, it may also be desirable to use a navigation sensor that is suitably sized for the instruments, implants or devices being employed. However, it may be difficult to construct a suitable position and orientation sensor assembly that provides the desired position and orientation information with the desired precision and accuracy and which is of a suitable size for use with or within the instruments, implants or devices in question.